RE: [PATCH v4 4/7] iommu/vt-d: Remove has_iotlb_device flag

[Tian, Kevin]

> From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Sent: Friday, August 9, 2024 1:54 PM
> 
> The has_iotlb_device flag was used to indicate if a domain had attached
> devices with ATS enabled. Domains without this flag didn't require device
> TLB invalidation during unmap operations, optimizing performance by
> avoiding unnecessary device iteration.
> 
> With the introduction of cache tags, this flag is no longer needed. The
> code to iterate over attached devices was removed by commit 06792d067989
> ("iommu/vt-d: Cleanup use of iommu_flush_iotlb_psi()").
> 
> Remove has_iotlb_device to avoid unnecessary code.
> 
> Suggested-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>

Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>